The recent technology transition from film to “electronic media” has spurred the rapid growth of the imaging industry with applications including still and video cameras, cell phones, other personal communications devices, surveillance equipment, automotive applications, computers, manufacturing and inspection devices, medical appliances, toys, plus a wide range of other and continuously expanding applications. The lower cost and size of digital cameras (whether as stand-alone products or imbedded in other appliances) is a primary driver for this growth and market expansion.
Most applications are continuously looking for all or some combination of higher performance (image quality), features, smaller size and/or lower cost. These market needs can often be in conflict: higher performance often requires larger size, improved features can require higher cost as well as a larger size, and conversely, reduced cost and/or size can come at a penalty in performance and/or features. As an example, consumers look for higher quality images from their cell phones, but are unwilling to accept the size or cost associated with putting stand-alone digital camera quality into their pocket sized phones.
One driver to this challenge is the lens system for digital cameras. As the number of photo detectors (pixels) increases, which increases image resolution, the lenses must become larger to span the increased size of the image sensor which carries the photo detectors. Also, the desirable “zoom lens” feature adds additional components, size and cost to a lens system. Zoom, as performed by the lens system, known as “optical zoom”, is a highly desired feature. Both these attributes, although benefiting image quality and features, add a penalty in camera size and cost.
Digital camera suppliers have one advantage over traditional film providers in the area of zoom capability. Through electronic processing, digital cameras can provide “electronic zoom” which provides the zoom capability by cropping the outer regions of an image and then electronically enlarging the center region to the original size of the image. In a manner similar to traditional enlargements, a degree of resolution is lost when performing this process. Further, since digital cameras capture discrete input to form a picture rather than the ubiquitous process of film, the lost resolution is more pronounced. As such, although “electronic zoom” is a desired feature, it is not a direct substitute for “optical zoom.”